1

Prepare Avocado Mayonnaise: Combine all ingredients in a food processor. Process; scraping down sides to work in ingredients until all is smooth. Cover and refrigerate until ready to use. Clean out processor bowl.

2

In food processor bowl, combine onions, cilantro, oil, juice, zest, sugar, jalapeño, salt and pepper. Process, then transfer to pyrex dish. Add fish steaks, cover, and marinate at room temperature, turning once or twice, for 1 hour.

3

Meanwhile, preheat gas grill to medium-high. Position grill rack 5 to 6 inches above heat. When grill is ready, remove steaks from marinade (reserve marinade), and lay them on the rack. Cover and grill, basting with marinade and turning once, until fish is done to your liking, about 8 minutes total for fish slightly undercooked at the center.

4

Transfer fish to plates, top with a dollop of the mayonnaise, and serve immediately.